Research‎ > ‎

4. In situ radiation

(1) SFT removal by nanotwinned Ag;
(2) Radiation induced twin boundary migration in nanotwinned Ag
(3) Capture of defect clusters by nanocrystalline Ni
(4) Defect migration kinetics in nanoporous Ag
(1) in situ radiation on nanotwinned Ag


(2) Radiation induced twin boundary migration in nanotwinne Ag





(3) in situ radiation on nanocrystalline Ni





(4) Superior radiation tolerance of nanoporous Ag

Radiation damage in CG and NP Ag


(5) Radiation damage in immiscible Ag/Ni nanolayers

Defect capture by Ag/Ni layer interface

(Downloaded over 100 times from Phil. Mag. website)


Removal of stacking-fault tetrahedra by twin boundaries in nanotwinned metals

K.Y. Yu, D. Bufford, C. Sun, Y. Liu, H. Wang, M.A. Kirk, M. Li, X. Zhang, Nature Communications, 4, 1377, (2013)


Highlights:
  • Effective removal of SFTs by twin boundaries
  • Lower radiation-induced defect density with smaller twin thickness
  • Twin boundary migration under radiation




K.Y. Yu, D. Bufford, F. Khatkhatay, H. Wang, M. Kirk, X. Zhang, , Scripta Mater, 69 (2013) 385.
  • A systematic in situ radiation study (in TEM) that shows frequent absorption of defect clusters by coherent and incoherent twin boundaries in nanotwinned Ag.

  • In situ observation of twin boundary migrations under radiation. This is in large contrast to annealing and stress induced twin boundary migration.

  • Discussion of several potential mechanisms that may lead to the migration of twin boundaries.



C. Sun, M. Song, K. Y. Yu, Y. Chen, M. Kirk, M. Li, H. Wang, X. Zhang, Metallurgical and Materials Transactions A, 44(2013):1966-1974


Highlights:
  • High angle GBs in nanocrystalline (NC) Ni effectively absorb irradiation-induced dislocation loops and segments.
  • High angle GBs significantly reduce the density and size of irradiation-induced defect clusters in NC Ni.

C. Sun, D. Bufford, Y. Chen, M. A. Kirk, Y.Q. Wang, M. Li, H. Wang, S. Maloy, and X. Zhang, Scientific Report 4 (2014) 3737.
Highlight
  • The first in situ TEM study to examine radiation damage in nanoporous (NP) metal  

  • Provides direct evidence that free surface in NP metal effectively absorb irradiation-induced defect clusters, and thus enables exceptional radiation tolerance

  • Determine, for the first time, global and instantaneous diffusivity of defect clusters in NP Ag

  • Discover an unexpected phenomenon: both global and instantaneous diffusivity are lower in NP Ag than in coarse-grained (CG) Ag.






K. Yu, C. Sun, Y. Chen, Y. Liu, H. Wang, M. Kirk, M. Li, X. Zhang, Philosophical Magazine, 93 (2013) 3547.

  • The first in situ experiment (both bright and dark field TEM) that shows frequent absorption of defect clusters by layer interface
  • Analytical model that explains the rapid migration of defect clusters toward interface
  • Size effect, that is smaller layer thickness enhances radiation tolerance significantly